Khuzd' pl. Khazâd was the Khuzdul word for the "Dwarves".
The word comes from the root Kh-Z-D; it is also visible in the words Khuzdul and perhaps Nulukkhizdîn.
The plural form Khazâd is the basis of Quenya casar and Sindarin hadhod.
The Adûnaic word hazad, meaning "seven", is presumably also related.